John Nielsen

Port Jefferson, NY: John Dennis Nielsen, of Port Jefferson, New York passed away peacefully on June 24, 2026. A devoted husband, father, grandfather, brother, and man of God, John leaves behind a legacy of love and dedication to family.

John was the beloved son of the late John and Madeline Nielsen and the cherished brother of Robert Nielsen and Jayne Nielsen.

He is survived by his loving wife of almost 40 years and partner of over 50 years, Renee Nielsen, with whom he built a beautiful life centered on faith and family.

John was an extremely proud and devoted father and is also survived by John Nielsen and his wife, Emma, Gregory Nielsen and his wife, Melissa, and Rachel Wilson and her husband, Jake.

Nothing brought John greater happiness than being “Grandpa” to his six grandchildren: Grayson McNally, Cameron Nielsen, Madeline Nielsen, Amelia Nielsen, Charlotte Wilson, and John M. Nielsen. His greatest joy in life was watching his children and grandchildren grow, cheering them on at countless sporting events, celebrating their accomplishments, and simply being present for every milestone.

John’s unwavering love was evident in his actions; he was always there when he was needed, ready to set aside whatever he was doing for the people he loved most. He dedicated many years of service to UPS, where he was known for his strong work ethic, reliability, and commitment. While he took great pride in his career, it was at home where his heart truly belonged. Whether relaxing in the backyard, gathering with loved ones, or simply enjoying everyday moments together, he treasured the time spent with his family above all else.

John will be greatly missed, but the love, faith, and values he shared will live on through his children, grandchildren, and all who knew him. His family finds peace in knowing he is now in God’s loving embrace.

In lieu of flowers, John's family kindly requests that donations be made to the Prostate Research Fund.